Gripper-finger mechanism for presses.



J. 0. 000K. GRIPPEB. FINGER MECHANISM FOR PRESSES.

APPLICATION FILED APR. 29, 1914'.

1,1 1 1,364. Patented 86 515.22, 1914,

UNITED STATES PATENT OFFICE.

JOHN C .-COOK, OF CHICAGO, ILLINOIS.

G-RIPPER-FINGER MECHANISM FOR PRESSES.

Specification of Letters Patent.- iPatented Sept. 2 2, 1914.

I App1icationfl1edApri129, 1914. Serial No. 835,064.

To all whom it may concern;

B6 it known that I, JOHN C. Coon, a citizen of the United States, and a resident of Chicago, in the countyof Cook and State of Illinois, have invented certain new and useful Improvements in Gripper-Finger Mechanism for Presses, of which the folnevertheless be capable of independent movement and adjustment, so that each; finger will-naturally engage the paper be-i heath it in spite of any variations that may exist in the thickness thereof at the diffe'rent points where the fingers engage the paper.

To illustrate my invention. I annex 'hereto a sheet of drawings, in which the same; reference characters are used to designate; identical parts in all the figures, of which- Figure 1--is a top plan view of a. portion; of a lithograph press having my invention;

applied thereto; and Fig. 2 is avertical section on an enlarged scale. I i

I have shown my invention as-applied to{ a lithograph press in which the plate (1. upon which the paperto be printed is placed 2 is a part of the main framework. Mounted in-bearings b secured on the top of the frame is the rod 0, upon which a plurality of gripper-fingers d are pivoted, as best seen in Fig. 2. These fingers have a stepped aperture 6 in the rearportion thereof, and a rod f, having a head thereon cooperating with the shoulder in the aperture e, extends down through each gripper, through an aperture 9 in the bed-plate, and rests on the eccentric shaft h, which is journaled in suitable bearings in the frame, and is provided with a handle 2' by which it may be rocked from one position to another. The lower ends of these rods f are guided in a bar 3' extending across the frame and having as many apertures therein through which the rods pass as there are rods. The upper end of the rod beneath the dog is surrounded by a loose sleeve is, which terminates in or extendsto a washer Z at the lower end thereof. A rather strong helically-coiled expanding spring m is interposed between the washer Z and an abutment n secured on the rod, which abutment preferably takes the form of 'a cupped nut screwed on the threaded lower end of the rod and secured in place by the lock-nut 0. Between the washer Z and the underside of the top-of the frame, I secure a much weaker helically-coiled expanding spring p. The action of the mechanism just described is as follows: The springs m are of such a length that when the handle 2' is turned to the position shown, in which it is stopped by the lug q secured on the handle cooperating with the stop-pin 1' on the frame, the high part of the eccentric engages the bottoms of the rods f and holds them up, as shown, so that the helicallycoiled' expanding spring m is compressed and acts on the washer Z to lift the same, and this in turn lifts the sleeve is, which lifts the rear end of the dog (1, so that the front end is forced down on the paper beneath it to hold it securely in position. The amount that this spring m is compressed is preferably less than the eccentricity of the bar it, so that when said bar is swung to the opposite position, in which the lug contacts with the other stop-pin s, the spring 72 cooperating with the washer l, and acting through the spring m and the nut n against the rod 7', forces said rod down, the rod being free to descend on account of the lower part of;the eccentric being uppermost. The action of this spring 79 thus forces the rod 7 down, and its head engages with'the shoulder in the aperture e,'and draws that end of the dog down, thus raising the front end so as to release the sheet of paper held thereby.

- It will be noted that, owing to the fact that each finger d is loose on the rod 0 and has its own springs, the dog can act certainly against the paper that may be be neath it, whatever its thickness may be relative to the paper beneath the other dogs. While I have shown and described my invention as embodied in the form which I at present consider best adapted to carry out its purposes, it will be understood that it is capable of modifications, and that I do not desire to be limited in the interpreta tion of the following claims except as may be necessitated by the state of the prior art. WVhat I claim as new, and desire to secure by Letters Patent of the United States, is:

With the plate, an eccentric rock-shaft, a

headed rod for each finger're'sting on the rock shaft and passing through an aperture ,in' the finger, and means for forcing the rod down to lift the fingers when the eccentric shaft is rotated to permit downward movement of the rod.

2. In.a device of the class described, the combination with a support, of a finger ivoted thereon, a headed rod passing oosely throu h an aperture in the finger, an eccentric shaft on which therod rests, means for rocking the shaft, and spring mechanism for holding the finger in engagement with the support. I

3. In a device of the class described, th combination with a support, of a finger pivoted thereon, a headed rod passing loosely through an aperture in the finger, an eccentric shaft on which the rod rests, means for rocking the shaft, a sleeve surrounding the rod and engaging the under side of the finger, and a helically-coiled expanding spring surrounding the rod and interposed between the lower end of the sleeve and an abutment on the rod.

4. In a device of the class described, the combination with a support, of a finger ivoted thereon, a headed rod passing oosely'through an aperture in the finger, an eccentric shaft on which the rod rests,

- means for rocking the shaft, a sleeve surrounding the rod and engaging the under side of the finger, and a helically-coiled exanding spring surrounding the rod and mterposed between the lower end of the sleeve and anabutment on the rod, said abutment consisting of a nut screwed thereon'so as to adjust the tension of the spring.

5. In a device of the class described, the combination with a support, of a finger pivoted thereon, a headed rod passing loosely through an aperture in the finger, an eccentric shaft on which the rod rests, means for rocking the shaft, a sleeve surrounding the rod and engaging the under side of the finger, a helically-coiled expanding spring surrounding the rod and interposed between the lower end of the sleeve and an abutment on the rod, and a second spring interposed between the bottom of the sleeve and the support. p

6. In a device of the class described, the combination with a plate, of a bearing rod supported above the plate,'a plurality of fingers independently pivoted on the rod cooperating with the plate and having apertures through the rear ends thereof, an eccentric rock-shaft located beneath the fingers, a headed rod for, each finger passing through the aperture therein and resting on the rock-shaft, an abutment on each rod, a helically-coiled expanding spring surrounding each rod and resting on the abutment, a washer ontop of each of said springs, a sleeve resting on each of said washers and engaging-the under side of the rear end of the finger associatedtherewith,

and a helically-coiled expanding. spring surrounding each sleeve and interposed between its washer and a stationary abutment. In witness whereof, I have hereunto set my hand and aflixed my seal, this 21st day of April, A. D. 1914:. v JOHN C. COOK. [1,. s.] Witnesses:

J 0111 1 HOWARD MCELROY, JNO. G. ELLIOTT. 

